IEC 61300-3-39:2011

Overview

IEC 61300-3-39:2011 is an international standard developed by the International Electrotechnical Commission (IEC) that defines procedures for selecting physical contact (PC) optical connector reference plugs used in return loss (RL) measurements. Specifically, it focuses on non-angled PC optical connector plugs, providing a method to choose reference plugs and establish acceptance return loss values for plug testing. As part of the IEC 61300 series on fibre optic interconnecting devices and passive components, this standard ensures consistent and reliable measurement of return loss, which is critical to evaluating the quality of fibre optic connections.

The 2011 edition supersedes the 1997 version with technical revisions involving the structure, general descriptions, and annex content. Its goal is to guarantee that two randomly mated PC optical plugs meet minimum return loss requirements for optimal performance in fibre optic systems.

Key Topics

• Reference Plug Selection: Defines a "reference plug" as a member of a group of minimum three plugs that, when mated in all combinations, yield a specified return loss (RL) value. This plug serves as the measurement baseline for return loss testing.

• Return Loss (RL) Measurement: The standard clarifies how to measure RL at the mating points of PC optical connectors, which is influenced by microscopic surface damage and refractive index variations caused during polishing. These factors create reflections affecting signal integrity.

• Acceptance Return Loss Value (RLa): To ensure any randomly mated plugs exceed a minimum acceptable RL, the standard establishes an acceptance RL value for plugs tested against the reference plug. This value depends on the reference plug's RL and the minimum RL allowed for random mated pairs.

• Intrinsic Return Loss (IRL): Introduces IRL as a theoretical parameter representing the return loss of a plug mated to itself. IRL helps derive the RL of connections formed by any two plugs, enabling the selection of suitable reference plugs.

• Measurement Procedure: Provides step-by-step methods to:

  • Select the reference plug from a group
  • Measure minimum acceptable RL of plugs under test
  • Consider accuracy and instrumentation requirements

• Mathematical Relationships: The standard includes critical formulas linking RL, RLa, and IRL values that underpin the testing methodology and acceptance criteria.

Applications

IEC 61300-3-39:2011 is essential for manufacturers, testers, and engineers working with fibre optic interconnecting devices and passive components, particularly those involved in quality control and specification compliance of optical connectors. Practical applications include:

• Quality Assurance in Connector Production: Ensuring plugs meet minimum return loss specifications before shipment or assembly.

• Connector Performance Verification: Validating that randomly mated PC optical connectors achieve required signal integrity and low reflection losses in field or laboratory conditions.

• Standardized Testing: Providing a reproducible and internationally recognized procedure for return loss measurements using reference plugs, supporting interoperability between devices from different suppliers.

• Fibre Optic Network Deployment: Assisting in the assessment of optical connectors to minimize link losses that hurt network performance and reliability.

• Research and Development: Offering benchmarking measurement techniques for new connector designs and polishing methods.

Related Standards

For comprehensive testing and measurement of fibre optic components, IEC 61300-3-39:2011 should be used alongside the following standards:

• IEC 61300-3-6: Basic test and measurement procedures - Return loss measurement methods for fibre optic connectors.

• IEC 61300 Series: Covers a wide range of tests and measurement protocols for fibre optic interconnecting devices and passive components.

• ISO/IEC Directives, Part 2: Provides the framework for the preparation and drafting of international standards.

Summary

IEC 61300-3-39:2011 sets the internationally accepted method for selecting physical contact (PC) optical connector reference plugs and defining acceptance return loss values for plug testing. By standardizing return loss testing protocols, it improves consistency, ensures quality, and supports reliable performance of fibre optic interconnections worldwide. The standard’s focus on non-angled PC connectors and its precise mathematical approach make it vital for industries and professionals committed to high-performance optical fibre networks. Implementing IEC 61300-3-39 helps guarantee that optical connectors meet stringent return loss criteria, enhancing system efficiency and longevity.